1. Field of the Invention
This invention relates to a sewing apparatus to which a thread held by a thread cassette is supplied so that a sewing operation is carried out.
2. Description of the Related Art
In conventional sewing apparatus such as sewing machines, a thread cassette holding a needle thread in a wound state is attached to a cassette mount provided in a body of the apparatus, as disclosed in U.S. Pat. No. 3,749,039 to Russell A. Fritts. When possessing a large number of thread cassettes, a user needs to grasp characteristic including a material, length and usage of the thread held in each thread cassette. The user manually sets sewing conditions (thread tension, sewing speed, etc.) suitable for each thread in view of the characteristics of each thread when sewing is carried out using each thread.
However, when a beginner, who may be unfamiliar with the material and the characteristics of the thread held in each thread cassette, uses a sewing apparatus, he or she sometimes cannot confirm a thread held in the thread cassette easily in case that a printed indication of thread material and the like have disappeared or the thread is not exposed from the thread cassette. In such a case, there is a possibility that sewing conditions suitable for the thread held in the thread cassette may not be set. Furthermore, setting sewing conditions suitable for the threads held in the respective thread cassettes is troublesome for users familiar with the sewing machines.